Physics/Math (1)/(f ) = (1)/(p) + (1)/(l) How do I derive "f"? Pleaseee help me​

Question

Physics/Math


`(1)/(f ) = (1)/(p) + (1)/(l)`
How do I derive "f"?
Pleaseee help me​

Answer 1

f = pl / (l + p)

Step-by-step explanation:

1/f = 1/p + 1/l

Find the common denominator of the right hand side.

1/f = l/(pl) + p/(pl)

Add:

1/f = (l + p) / (pl)

Take the inverse of both sides:

f = pl / (l + p)